Process for concentrating ore materials



Patented Mar. 31, 1942 David Walker Jayne, In, Old Greenwich, Stephen Edward Erickson,

Springdale,

and Harold Milton Day, Cos Cob, Conn., assignors to American Cyanamid Company,

New Yor;

N. EL, a corporation of Maine No Drawing. Application March 30, 1940, Serial No. 326,953

12 Claims.

The present invention relates to mineral concentration. More particularly it relates to a new class of reagents for selectively separating acidic minerals from ore materials.

Still more particularly it relates to the use of fatty acid esters of sulfonic acid salts of amino alcohols and/or mixtures with the reaction products of polyalkylene polyamines with fatty acids or fatty acid glycerides or other esters, and the substantially water soluble salts of such products, as promoters or collectors for acidic minerals in froth flotation, film flotation, stratification, agglomeration, tabling, and related mineral separation processes. While the present invention is not limited to any particular ore concentrating process or to any particular ore, its most important field of usefulness is in connection with froth flotation processes of separating silica or silicate minerals, such as mica, from non-metallic ores such as limestone, bauxite, barytes, ilmenite, calcite, and the like, and especially phosphate minerals.

A recent development in processes for the concentration of ores is one in which the so-called cationic reagents are used as promoters or collectors for acidic silicious gangues to effect a separation from the ore values. The use of these cationic reagents has resulted in a more economical and efficient method of recovering the ore values from a number of ore materials and particularly in connection with phosphate bearing ores in which the silicious gangue is floated away from the phosphate minerals.

In accordance with this invention natural ores or artificial materials comprising a mixture of acidic minerals with other mineral constituents are subjected to a separation or concentration process in the presence of a promoter for the acidic ore minerals. said promoter being fatty acid esters of the sulfonic acid salts of amino alcohols or a mixture of these salts with the condensation products of polyalkylene polyamines and fatty acids or the salts of such products, to effect a separation of the acidic minerals from the other ore constituents.

The present invention relates to an entirely new class of promoting or collecting reagents for acidic minerals. These new reagents are pro moters for negatively charged or acidic ore mago of actual ions.

with different acidic ore materials and with the different reagent combination used. In the past various theories have been advanced as to the manner in which some acidic silicious promoters worked, one of which was that positively charged surface active ions had a strong aflinity for anionic or acidic minerals and hence they are sometimes loosely referred to in the art as cationic reagents.

We have found that it is not necessary to the present invention to use salts as similar results are obtained with the substantially non-water soluble products, provided satisfactory dispersion and distribution is efiected. The present invention is accordingly not intended to be limited in any way to the use of a silica promoter which is highly ionized. The interaction between the surface of the silica and the promoter does not appear to be tied up exclusively with the presence Th theory advanced in the prior art does not therefore appear to be correct as applied to silica flotation, or at least it does not appear to be a necessary factor in the present invention. We do not wish to advance any definite theory of action in silica flotation and the present invention is not intended to be limited to any particular theory of the so'called cationic reagents.

The compounds that have been found to have a selective filming attraction for acidic minerals and are useful in carrying out the present invention include broadly the reaction products of organic sulfonic acid salts of amino alcohols with fatty acids, either alone or mixed with the reaction products of polyalkylene polyamines with fatty acids or fatty acid glycerides and salts of these reaction products. A general method of reacting organic sulfonic acid salts of amino alcohols with fatty acids and the resulting products are claimed in the copending Jayne and Day apduce esters or condensation products thereof.

The reaction proceeds smoothly between either the aliphatic sulfonic acid salts or aromatic sulfonic acid salts of amino alcohols with fatty acids. In the preferred embodiment of the presterials. The promoter action will, of course, vary 8 i inve n. however, the aromatic sulfonic acid salts of straight chain primary amino alcohols are reacted with higher fatty acids. These preferred compounds are entirely compatible the esters are produced by heating mixtures of the substances to about zoo-250 C. whereupon water is split out and the fatty acid ester of the aromatic sulfonic acid salt of the amino alcohol is formed. For example. if a mixture of 30 grams of the p-toluene sulfonic acid salt of monoethanolamine and 30 grams of myristic acid (1:1 molar ratio) is heated in an open beaker to 250 C., a light brown, soft, waxy material is obtained which is completely soluble in water, to give "soapy" solutions which have wetting-out emulsifying, and dispersing properties.

While the compounds of the present invention are most probably esters, we do not desire to limit the invention by such a positive designation and prefer therefore to broadly include any or all products produced by the reaction of either aliphatic or aromatic sulfonic acid salts of amino alcohols with fatty acids. The preferred fatty acids are those containing at least 8 carbon atoms and especially the fatty acids of animal and vegetable origin which contain at least 10 carbon atoms. The fatty acids may be either saturated or unsaturated and may or may not be hydroxylated.

Other carboxylic acids which may be used in place of all or part of the myristic acid in the above example, are capric, palmitic, stearlc, oleic, abietic, montanic, naphthenic acids, talloel acids, mixtures of such acids and especially mixtures of acids obtainable by saponiflcation from coconut oil, palm kernel oil, cottonseed oil, or from any of the various other vegetable or animal oils and fats.

Likewise, various other organic sulfonic acid salts of amino alcohols may be used in place of all or part of p-toluene sulfonic acid salt of monoethanolamine in the above example, and the invention is not limited to those of a particular series. Thus, for example, in addition to the common aromatic sulfonic acid of the benzene series employed in the example, those of diphenyl, naphthalene, anthracene, phenanthrene series may be used. The aliphatic sulfonic acids may likewise be employed such as those of paraflin hydrocarbons of 12-18 carbon atoms in length, ligninsulfonic acid, guanyl urea sulfonic acid, dodecyl sulfonic acid, and the like, also compounds such as toluene thiosulfonic acid.

Representative amino alcohols which may be employed in preparing the organic sulfonic acid salts in addition to mono-ethanolamine and which may be used in place of all or part thereof are monopropanol amine, dipropanol amine, diethanolamine, mono-isopropanol amine, di-isopropanol amine, mono-butanol amine, mono-isobutanol amine, and various other alkyl amino alcohols such as:

2 methyl 2 hydroxy 1 amino propane 2 methyl 2 hydroxy 4 amino butane 2 methyl 2 hydroxy 5 amino pentane 2 methyl 2 hydroxy 6 amino hexane Hydroxyethyl ethylene diamine 2 amino 1 butanol 2 amino 2 methyl 1 propanol 2 amino 2 methyl 1,3 propanediol 2 amino 2 ethyl 1,3 propanediol Tri (hydroxy methyl) amino methane or any amino alcohol or derivative thereof having at least one amino group capable of forming a salt with an organic sulfonic acid and at least one hydroxy group capable of forming an ester with a carboxylic acid.

While these reaction products as described above are good promoters for acidic ore materials, we have found that when mixtures with the polyalkylene polyamine condensation products of fatty acids are used. the results are better than those produced when used separately.

The polyalkylene polyamine fatty acid condensation products in the present invention are claimed as an ingredient of a specific nature. A general method for their preparation comprises heating a fatty acid, glyceride. or the like, with a polyalkylene polyamine at a temperature of from -250 C. until the reaction is complete.

The products are usually homogeneous viscous pastes which combine with acids such as formic, acetic, hydrochloride, and the like, to yield salts which are soluble in water. These reaction products are those most probably represented by the following general formula:

Y-CO-NH-A-Z in which A represents the group CI-lRCHR'-NH or two or more such groups serially arranged, R and R may be hydrogen, an alkyl, amino, or amino acidyl radical, Y stands for an aliphatic hydrocarbon radical containing at least nine carbon atoms which hydrocarbon radical may contain one or more double bonds and may be substituted by hydroxy groups, and Z stands for hydrogen or the acidyl radical of an aliphatic fatty acid containing at least ten carbon atoms, and the acid salts of such compounds.

Representative polyalkylene polyamines which may be employed for condensing with the fatty acids are diethylenetriamine, dipropylenetriamine, dibutylene triamine, triethylene tetramine, tetraethylene pentamlne, or mixtures of any two or more of such polyamines either as relatively pure compounds or crude mixtures.

Either the saturated, unsaturated, or hydroxy fatty acids may be employed for reacting with the polyamines, the preferred ones being those having at least nine carbon atoms, for example, lauric, palmitic, stearic, oleic, ricinoleic, capric, myristic, mixtures of such acids and especially mixtures of the fatty acids obtained from the fats and oils of either vegetable or animal sources or their glycerides such as those in coconut oil, palm oil, palm kernel oil, cotton seed oil, corn oil, linseed oil, olive oil, peanut oil, fish oils, and the like.

The compounds used in the present invention are not limited to those produced by reacting any particular molecular ratio of the polyalkylene polyamine to the fatty acid, but preferably they are the monoacidyl or they may be crude mixtures which may contain an excess of either the polyalkylene polyamines or the fatty acid substances.

The reagents of the present invention are effective promoters or collectors for negatively charged or acidic ore materials generally and said acidic materials may either be worthless gangue or valuable ore constituents. The most important uses are, however, in connection with the froth flotation of silica from non-metallic ores in which the silicious gangue may represent a minor proportion of the ore rather than metallic and sulfide ores in which the gangue usually represents the major proportion of the ore. Representative acidic ore materials are'the feldspars, quartz, pyroxenes, the spinels, biotite,

but are also economical in amounts used. The

quantities required range from 0.2 pound to 2.5

pounds per ton of ore depending upon the particular ore and the particular reagent. The invention is not, however, limited to such quantities.

The reagents of the present invention may be used alone or in mixtures with other promoters. They may likewise be used in conjunction with other cooperating materials such as conditioning reagents, activators, frothing reagents, depressing reagents, dispersing reagents, oily or fat materials such as hydrocarbon oils, fatty acids, or fatty acid esters.

These new reagents are also adaptable for use in any of the ordinary concentrating processes such as fllm flotation, tabling, and particularly in froth flotation operations. The ore concentrating processes employed will depend upon the particular type or kind of ore which is being processed. For example, in connection with phosphate rock, relatively coarse phosphate bearing material, for example, 28 mesh and larger, can be very economically concentrated by using these reagents in conjunction with a material such as fuel oil or pine oil and subjecting to concentration by the use of tables or by film flotation. The 28 phosphate rock material is best concentrated by means of froth flotation employing these improved silica promoters.

concentration operation. They may also be stage fed into the flotation circuit.

Other improved phosphate flotation features which are known may be utilized in connection with the present invention such as splitting the phosphate flotation feed into a plurality of size ranges and floating each size separately as described in the U. S. Patent No. 2,156,245, thevery complete removal of the slime prior to flotation which is also an aid to better results as pointed out in the Erickson application, Serial No. 325,011, flied March 20, 1940, and the Mead and Maust application Serial No. 320,121, filed February 21, 1940 which describes a process for classifying and desllming phosphate flotation feed by means of a hindered settling classifier and which deslimed feed is well suited for treatment in accordance with this invention.

The invention will be further illustrated by the following specific examples which are illustrations of the preferred embodiments thereof, but is not to be strictly limited thereby.

Example 1 Flotation tests as follows were made on a sample of Florida phosphate ore from the Old Colony mine near Brewster. This ore material. which was essentially -48 +200 mesh material was agitated and scrubbed with water to break up the clay balls. The slimes were subsequently removed by decantation and washing repeated until the ore material was substantially free of slimes.

Separate 600 gram samples of the deslimed flotation feed were diluted to 20% solids with water and transferred to a laboratory size Fagergren flotation machine. The particular reagent or reagent combination was added to the pulp. The machine was started up and the pulp and reagent mixed for five seconds. Air was then admitted to the machine and the resulting concentrate was skimmed off for three minutes. The flotation test products were then filtered. dried, weighed and assayed. The metallurgical data obtained in these tests are presented in Table I.

Table I Concentrate Tailing Test Fecd R eaction roduct Feed wt Insol Dist. Wt hm] Dist. p

' insol. insol.

Percent Percent Percent Percent Percent Percent Percent Lbs. per ton l 59. 07 59.08 92. 76 92. 78 40. 92 10. 42 7. 22 Reaction Product of lauric acid with the p-toluene sul- 2. 50 ionic ac d salt of ethanolamine. 2 58.70 55.28 93. 52 87.98 44. 72 15.80 12.02 Reaction product of myristic acid with the p-toluene 2.50

sulfonic acid salt of ethanolamiue. 8 58. 38 50. 52 93. 66 90. 68 43. 48 12. 52 9. 82 Reaction product of coconut fatty acid with the ptoluene 2. 00

sulfonic acid salt of ethanolamine. 4 58. 28 55. 03 92. 80 87. 62 44. 97 16. 04 12. 38 Reaction product of capric acid with the benzene sulfonic 2. 00

acid salt of ethanolamine. 5 58. 65 57. 34 93. 28 91. 20 42. 66 l2. l0 8. 80 Reaction Product of capric acid with the p-toluene sul- 2.00

Ionic ac d salt of ethanolaxnine.

When the reagents of the present invention are employed as promoters in the froth flotation of silica from phosphate rock, which is the preferred embodiment thereof, the condition may be varied in accordance with procedures known to those skilled in the art. The reagent may be employed in the form of aqueous solutions, emulsions, mixtures, or solutions in organic solvents, such as alcohol and the like. The reagent may be introduced into the ore pulp in the flotation cell without prior conditioning or they may be Example 2 Another series of tests was run on a different sample of phosphate rock from the Old Colony mine. In this test mixtures of the reaction products of aromatic sulfonic acid salts of amino alcohols and fatty acids with fatty acid condensation products of polyalkylene polyamines were employed as silica promoters. The original sample used in these tests contained less slime than the sample used for the preceding tests.

conditioned with the ore pulp prior to the actual The testing procedure, scrubbing, desllming and flotation, used for this scrim of tests was the same as that followed in the previous tests. The metallurgical data obtained in these tests is found in Table II.

acting organic sulfonic acid salts of amino alcohols having at least one free hydroxy group with V a fatty acid having at least 8 carbon atoms.

5. In the froth flotation process of separating Table II Concentrate 'lailing Test Feed Rem!" g t d N insol. Weight Insol. 3%; Weight ID801- 13 i Per cent Per cent Per cent Per cent Per cent Per cent Per cent Acetate of the reaction product of diethylene triarnine Ilia/ton Feed 42 7 mos andcoconutoil 0.83 1 53 a m Reaction product of coconutlattyacid with the p-toluene aulionic acid slit of ethanol amine 0. 67 Acet sits oi the or a action product of dicthylene triamine o w an 2 72 56 so 89 44 n Reaction product of coconut fatty acid withthep-toiuene aulionlc acid salt of ethanolamine v 0. b Acetate of the re action product of diethylene triamine o 67 an t n 3 42 51 54 Reaction product oicoconutiatty acid with the p-toluene sulionic acid salt of ethanoiamine 0. 33

While the foregoing examples relate to the separation of quartz from phosphate bearing material the invention is not limited thereto. Good recovery and separation are also obtained using our reagents and reagent combinations in connection with other silicious acidic minerals, for example, the separation of feldspar from quartz, mica from quarts, mice. from cement rock and the like.

We claim:

1. In ore concentrating processes utilizing differential surface wettability principles of separating acidic siliceous gangue from non-metallic ore constituents the process which comprises carrying out the concentration operation in the presence of products obtained by reacting organic sulfonic acid salts of amino alcohols having at least one free hydroxy group with a fatty acid having at least 8 carbon atoms.

2. In ore concentrating processes utilizing differential surface wettability principles of separating acidic siliceous gangue from phosphate rock values the process which comprises carrying out the concentration operation in the presence of products obtained by reacting organic sulfonic acid salts of amino alcohols having at least one free hydroxy group with a fatty acid having at least 8 carbon atoms.

3. In froth flotation processes of separating acidic siliceous gangue from non-metallic ore values the process which comprises subjecting the ore to froth flotation in the presence of products obtained by reacting organic sulfonic acid salts of amino alcohols having at least one free hydroxy group with a fatty acid having at least 8 carbon atoms.

4. The froth flotation process of separating acidic siliceous gangue from phosphate ore values which comprises subjecting the ore to froth flotation in the presence of products obtained by reacidic siliceous gangue from phosphate ore values the step which comprises subjecting the ore to froth flotation in the presence of the reaction product of the para toluene sulfonic acid salt of monoethanolamine with coconut oil fatty acids.

6. In the froth flotation process of separating acidic siliceous gangue from phosphate ore values the step which comprises subjecting the ore to froth flotation in the presence of the reaction product of the para toluene sulfonic acid salt of monoethanolamine with myristic acid.

'1. In the froth flotation process of separating acidic siliceous gangue from phosphate ore values the step which comprises subjecting the ore to froth flotation in the presence of the reaction product of the para toluene sulfonic acid salt of monoethanolamine with palm kernel oil fatty acids.

8. A process according to claim 5 in which a reaction product of diethylenetriamine with coconut oil fatty acids is also present.

9. A process according to claim 6 in which a reaction product of diethylenetriamine with myristic acid is also present.

10. A process according to claim '7 in which a reaction product of diethylenetriamine with palm kernel oil fatty acids is also present.

11. A process according to claim 3 in which at least one of the condensation products obtained by reacting a polyalkylene polyamine with a higher fatty acid or a salt of such condensation product is also present.

12. A process according to claim 4 in which at least one of the condensation products obtained by reacting a polyalkylene polyamine with a higher fatty acid or a salt of such condensation product is also present.

DAVID WALKER JAYNE, JR. STEPHEN EDWARD ERICKSON. HAROLD MILTON DAY. 

